Any search engine works by processing the search query entered by the user and returning a set of search results that matches the user intent. Search engines completes this task with the help of a collection of algorithms which are together known as Ranking algorithm. In one of the recent patents assigned to Google, it has been suggested that Google might use 2 different scores for ranking the web documents. These scores are described below:
Global Ranking Score
A global ranking score is computed for web documents/objects responsive to the search query, wherein each web object includes at least one web page from a cluster of web pages of corresponding websites.
Implementations can include any or all of the following features. The global ranking score for a particular website is computed based on data identified without reading information from the particular website. The score is determined based on both off site and on site data. Global ranking score computation includes calculation of off site data like number of links to a web page or website from other unrelated websites, the number of times users have selected the web page or website in search results responsive to a particular query, or other statistical data providing information regarding the relevance or authority of a particular website associated with the web object.
Onsite data may include data based on the number of keywords on the web page or website responsive to the search query, the location of the responsive keywords, a number of links to the web page from other web pages having the same domain, and/or the placement of the web page in the structure of the website.
Onsite Ranking Score
Onsite ranking scores are computed for web pages of a particular website in the responsive web objects, wherein computing the onsite ranking score includes evaluating an importance of at least one web page relative to other web pages within the particular website. Consider the scenario when more than 1 pages of a similar website competes together to rank for a particular search query then in such cases, the on site ranking score is computed and only the best result/object from among a cluster of results from similar domain is identified and displayed before the user.
How Google Applies Global Ranking Score and Onsite Ranking Score For Returning Search Results:
Step 1 - Receive a search query
Step 2 - Global ranking scores are computed.
Step 3 - Onsite ranking scores for webpages of a particular website are computed.
Step 4 - Identifying representative webpages of particular website based on onsite ranking scores.
Step 5 - Compare the strength of onsite ranking score Vs global ranking score. If the scores are consistent the program ends else the global ranking score of that particular website is adjusted based on the comparison of onsite ranking score.
Have a look at the below figure for understanding this behaviour in more detail: